package com.thealgorithms.maths;

public class DistanceFormula {
	public static double euclideanDistance(double x1, double y1, double x2, double y2) {
		double dX = Math.pow(x2 - x1, 2);
		double dY = Math.pow(y2 - x1, 2);
		double d = Math.sqrt(dX + dY);
		return d;
	}

	public static double manhattanDistance(double x1, double y1, double x2, double y2) {
		double d = Math.abs(x1 - x2) + Math.abs(y1 - y2);
		return d;
	}

	public static int hammingDistance(int[] b1, int[] b2) {
		int d = 0;

		if (b1.length != b2.length) {
			return -1; // error, both array must be have the same length
		}

		for (int i = 0; i < b1.length; i++) {
			d += Math.abs(b1[i] - b2[i]);
		}

		return d;
	}

	public static double minkowskiDistance(double[] p1, double[] p2, int p) {
		double d = 0;
		double distance = 0.0;

		if (p1.length != p2.length) {
			return -1; // error, both array must be have the same length
		}

		for (int i = 0; i < p1.length; i++) {
			distance += Math.abs(Math.pow(p1[i] - p2[i], p));
		}

		distance = Math.pow(distance, (double) 1 / p);
		d = distance;
		return d;
	}
}
